Design method of worn rail grinding profile based on Frechet distance method

2021 ◽  
pp. 095440972110496
Author(s):  
Fengtao Lin ◽  
Liang Zou ◽  
Yang Yang ◽  
ZhenShuai Shi ◽  
Songtao Wang
Keyword(s):  
Dynamic Characteristics ◽  
Design Method ◽  
Dynamic Performance ◽  
Calculation Model ◽  
Fréchet Distance ◽  
Distance Method ◽  
Rail Wear ◽  
Rail Grinding ◽  
Frechet Distance ◽  
Standard Profile

Due to the large volume and high running density of railway freight lines, rail deterioration occur frequently. Thus, it is necessary to grind the rail in time to improve the wheel-rail relationship. The profile data of the worn rail were measured at different measuring points in a section, and the Frechet distance method was adopted to analyze the data. The representative profile reflecting the overall condition of rail wear in this section is obtained. Combined with NURBS curve theory, a fitting algorithm in which the rail profile with certain discrete points was established. Taking the reduction of the amount of grinding material removed as the objective function, setting wheel-rail matching characteristics, and the reduction of rail wear as the constraint conditions, a calculation model for rail grinding profile was established. The dynamic characteristics of standard profile CN75 and g grinding profile OP75 were analyzed by the vehicle track dynamics model. The results showed that compared with the standard profile CN75, the amount of grinding material removed of the grinding profile OP75 is reduced by 44.7%, and the height reduction of the rail top is reduced by 0.39 mm. After [Formula: see text] km of running, the wear amounts of grinding profile OP75 is about 36.1%–36.5% less than that of standard profile CN75.In the small curve section, the derailment coefficient of grinding profile OP75 is reduced by 11.7% compared with that of standard profile CN75. The dynamic performance is improved. The grinding target profile has better dynamic characteristics and is beneficial to reduce wheel-rail wear.

Design method of rail grinding target profile based on non-uniform rational B-spline

2020 ◽  
pp. 095440972097281
Author(s):  
Fengtao Lin ◽  
Songtao Wang ◽  
Hai Zhang ◽  
Weihao Hu
Keyword(s):  
Service Life ◽  
Design Method ◽  
Dynamic Performance ◽  
Optimization Method ◽  
Maintenance Cost ◽  
Reconstruction Method ◽  
B Spline ◽  
Rail Wear ◽  
Rail Grinding ◽  
Train Operation

The grinding strategies for worn rails have a significant influence on the service life and maintenance cost of railways. Current grinding strategies, grinding the worn rails to their original profiles, leads to excessive amount of material removed and reduction of rail service life. Based on Non-Uniform Rational B-Spline theory (NURBS), which contributes to the control of curve smoothness, a rail profile reconstruction method was established considering the geometrical characteristics of the rail profile. The design of economical grinding rail profile can be achieved by using optimization method, which regards the amount of material removed and derailment coefficient as objectives, aiming at reducing rail wear. A new rail profile can be designed by integration of Archard wear model, FE contact model and vehicle-track coupling dynamic model. The result indicated that the wear of left and right rail is reduced by 29.26% and 31.06% compared with original CN60 profile, respectively. With the new rail profile, the dynamic performance is improved, and the contact stress, fatigue index and the amount of material removed is reduced. This optimized rail grinding profile contributes to the reduction of rail wear and guarantees the safety of train operation.

Finite Element Analysis and Optimization of Long-Span Gantry NC Machining Center Structure

2011 ◽  
Vol 346 ◽  
pp. 379-384
Author(s):  
Shu Bo Xu ◽  
Yang Xi ◽  
Cai Nian Jing ◽  
Ke Ke Sun
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Design Method ◽  
Dynamic Performance ◽  
Plate Thickness ◽  
Element Model ◽  
Wall Structure ◽  
Characteristic Analysis ◽  
Element Analysis ◽  
Dynamic Performance Analysis

The use of finite element theory and modal analysis theory, the structure of the machine static and dynamic performance analysis and prediction using optimal design method for optimization, the new machine to improve job performance, improve processing accuracy, shorten the development cycle and enhance the competitiveness of products is very important. Selected for three-dimensional CAD modeling software-UG NX4.0 and finite element analysis software-ANSYS to set up the structure of the beam finite element model, and then post on the overall structure of the static and dynamic characteristic analysis, on the basis of optimized static and dynamic performance is more superior double wall structure of the beam. And by changing the wall thickness and the thickness of the inner wall, as well as the reinforcement plate thickness overall sensitivity analysis shows that changes in these three parameters on the dynamic characteristics of post impact. Application of topology optimization methods, determine the optimal structure of the beam ultimately.

Dynamics Characteristics for Contact Surface of Machine Tool

2014 ◽  
Vol 538 ◽  
pp. 91-94
Author(s):  
Wei Ping Luo
Keyword(s):  
Machine Tool ◽  
Dynamic Characteristics ◽  
Contact Surface ◽  
Dynamic Performance ◽  
Virtual Prototype ◽  
Prototype Model ◽  
Ansys Software ◽  
Dynamic Analyses ◽  
Contact Surfaces

A virtual prototype model of Machine Tool has been constructed by using the Pro/E software and the ANSYS software. Considering the effects of contact surfaces, dynamic analyses of Machine Tool are studied. The effects of contact surfaces on the dynamic characteristics of machine tool are studied. So that the purpose predicting and evaluating synthetically the machine tool dynamic performance without a physical sample can be achieved.

Analysis and Optimization of the Static and Dynamic Characteristics of Head Frame

2011 ◽  
Vol 418-420 ◽  
pp. 2055-2059 ◽  
Author(s):  
Yu Lin Wang ◽  
Na Jin ◽  
Kai Liao ◽  
Rui Jin Guo ◽  
Hu Tian Feng
Keyword(s):  
Machine Tool ◽  
Dynamic Characteristics ◽  
Maximum Stress ◽  
Dynamic Performance ◽  
Mode Shapes ◽  
Cnc Machine ◽  
Static And Dynamic Characteristics ◽  
Maximum Deformation ◽  
Improvement Measures ◽  
Optimal Measure

The head frame is a key component which plays a supportive and accommodative role in the spindle system of CNC machine tool. Improving the static and dynamic characteristics has profound significance to the development of machine tool and product performance. The simplified finite element modal is established with ANSYS to carry out the static and modal analysis. The results showed that the maximum deformation of the head frame was 0.0066mm, the maximum stress was 3.94Mpa, the deformation of most region was no more than 0.0007mm, which all verified that the head frame had a good stiffness and deforming resistance; several improvement measures for dynamic performance were also proposed by analyzing the mode shapes, and the 1st order natural frequency increased 7.33% while the head frame mass only increased 1.58% applying the optimal measure, which improved the dynamic characteristics of the head frame effectively.

Development of High-Speed Response Electromagnetic Linear Actuator Using for Pneumatic Control Valve

2014 ◽  
Vol 532 ◽  
pp. 41-45 ◽  
Author(s):  
Myung Jin Chung
Keyword(s):  
Optimal Design ◽  
Dynamic Characteristics ◽  
High Speed ◽  
Design Method ◽  
Control Valve ◽  
Design Parameters ◽  
Linear Actuator ◽  
Analytic Model ◽  
Electromagnetic Linear Actuator ◽  
Quadratic Programming Method

Analytic model of electromagnetic linear actuator in the function of electric and geometric parameters is proposed and the effects of the design parameters on the dynamic characteristics are analyzed. To improve the dynamic characteristics, optimal design is conducted by applying sequential quadratic programming method to the analytic model. This optimal design method aims to minimize the response time and maximize force efficiency. By this procedure, electromagnetic linear actuator having high-speed characteristics is developed.

An Integrated Joint Dynamics System for Elastically Jointed Structures

1991 ◽  
Author(s):  
Y. Rong ◽  
H. S. Tzou
Keyword(s):  
Dynamic Characteristics ◽  
Dynamic Performance ◽  
Measuring Device ◽  
Joint Friction ◽  
Vibration Data ◽  
Unit Structure ◽  
Joint Dynamics ◽  
Joint Clearances ◽  
Stochastic Simulator ◽  
Vibration Measuring

Abstract The dynamic behavior of elastic joints strongly affect the dynamic performance of a jointed mechanical system. The dynamic contacts introduced by joint clearances create a system with nonlinear characteristics. Special effort needs to be made to study jointed mechanical systems. This paper presents an integrated joint dynamics system, which can be used to predict the dynamic characteristics of a newly designed structure, or to analyze an existing jointed structure. This joint dynamics system can also be applied as a real time monitoring and diagnosis system when it is connected with a vibration measuring device. The joint dynamics system includes: 1) a theoretical model of jointed structures, in which the joint clearance and joint friction effects are considered; 2) a stochastic simulator which is used to generate vibration data and evaluate system dynamic characteristics; 3) a diagnostic monitoring algorithm for vibration state detection; and 4) a forecasting vibration control scheme. The joint dynamics system is applied to the dynamic analysis of a truss-cell unit structure. The results presented in this paper show that the joint dynamics system is effective.

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